Seuthe in a hornby R3245TTS

[keith40]

Hi all I have fitted a Seuthe smoke unit 22 to a hornby R3245TTS 

at first it worked fine but now I can not turne the smoke unit off does any one have any ideas or have had simular problems?? 

Thanks keith

[Chrissaf]

IMHO....I suspect that you have probably damaged the output circuit of that particular function of the TTS decoder. If you continue to run the TTS loco with the Seuthe still connected, then you may risk irreparable damage to the rest of the TTS decoder. I am assuming, since you never said otherwise, that the loco is still controllable and the sound still presently works.

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The Seuthe 22 is rated at 120mA,  I am fairly certain that the 120mA rating of the written Seuthe 22 specification relates to the current drawn when at operating temperature. When cold, at instance of turn on, it will draw more. As it heats up, the resistance will increase therefore dropping the current to the 120mA figure. Most decoder functions are rated on average at 100mA max. Most likely, the function output semi-conductor component has burnt out and become short circuit, allowing the current to flow to the Seuthe unhindered. Continuing to operate the decoder with the Seuthe still connected is likely to stress the other decoder components in the surrounding circuitry.

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In general, when fitting a Seuthe you need to use a suitable decoder with an appropriate function current rating. The Hornby Sapphire for example, supports 200mA on the function OR fit a micro-relay interface, so that the function operates the micro-relay that in turn connects track voltage to the Seuthe. Thereby eliminating the need for the decoder to provide the Seuthe operating current directly.

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Officially, you can't buy TTS decoders from Hornby for self installation (although they do come up occasionally second-hand on e-Bay) . If you have damaged it by fitting a Seuthe, then I doubt that will be covered under Warranty.

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I believe others on here have fitted Seuthes to TTS models, thus they may have a different view to myself on this matter. If their's work fine with a direct connection to the Seuthe, then IMHO they may have been just lucky.

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IMHO - In My Humble or Honest Opinion

[Chrissaf]

Keith, have a look at this previous thread. In particular the reply by 'blackbird' at the bottom.

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https://www.hornby.com/uk-en/forum/smoke-unit-with-tts-stemers/?p=1/

[keith40]

Ok thank you chrissaf I wil look at all that 

why are hornby so unhelpful 

thanks keith 

[96RAF]

 

why are hornby so unhelpful 

Thats a bit unfair on Hornby as it failed when you overloaded it.

 

The current limitation is plain to see in the TTS decoder manual, both in the spec where it says unprotected and there is a separate paragraph about current limitation.

 

Perhaps Hornby should have written in large letters - if you overload this decoder it may fail.

[keith40]

I am not blaming hornby but when you phone them about this problem to try and understand what happened they say you modified a loco so it is not are problem that is unhelpful 

[trainlover23]

I am not blaming hornby but when you phone them about this problem to try and understand what happened they say you modified a loco so it is not are problem that is unhelpful 

Perfectly reasonable response from Hornby. You modified the model and you are responsible as their warranty is null and void.

[poliss]

Not really reasonable. The function wires are on the decoders for a reason. So you can add extra functions such as lights and smoke. Adding a smoke unit isn't modifying anything. It's making use of the function wires.